Electronic properties of poly(3-hexylthiophene)/ N-type silicon heterojunctions

Summary form only given. Heterojunction devices consisting of poly(3-hexylthiophene) (P3HT) and n-Si were fabricated by casting the polymer on a Si substrate. In this paper, the electronic properties of the slightly doped P3HT / n-Si junctions are discussed. The fabricated devices showed the rectifying characteristics (the rectifying ratio: more than 1000). The band structures of P3HT, which were determined from the cyclic voltammograms and the absorption spectra, can explain the rectifications. The plots of log I versus forward voltage gave a straight line, but the slope was independent of temperature. Apparently, the I-V characteristics are controlled by the mechanism of multistep tunneling recombination.